Issac - personally, I don't adhere to any 'typical' keynote presentation. Unless the conference organisers specifically state an exact content and time etc - then the keynote is an open invitation to showcase that keynotes standing and expertise related to the conference themes. Tht can range from a personal and anecdotal account of ones life story and journey to date (usually the most interesting and humorous) - through to a specific account of recent/current research projects.